There is a common need for electronic devices to be sealed so that the internal components of the electronic device are isolated from the external environment. This need is particularly important in portable electronic devices, such as portable electronic test equipment, which may be used in wet or dirty environments.
It is fairly easy to provide an adequate seal for electronic devices housed in a case having only two parts or sections, such as a top part and a bottom part. Two-part cases can be fabricated with a resilient gasket positioned between opposed marginal edges. The two parts are then drawn toward each other, thereby compressing the gasket between the opposed marginal edges.
Although the above-described technique works well for most two-part electronic device cases, it does not always work well for electronic device cases having multiple parts if any part contacts two or more parts of the case. The difficulty arises at the locations where three or more parts of the case join each other and one of the parts crosses over a gasket positioned between two other parts. Under these circumstances, there may be a gap where a gasket positioned between two of the parts extends over a gasket that is positioned between a third part and one or both of the two parts. As a result, it has heretofore been difficult to effectively seal many three-part electronic device cases from the external environment.
It would be possible to effectively seal multiple part electronic device cases despite the presence of a junction between three or more parts by using a single gasket having multiple branches or loops so that there could not be a gap where one part of the cases bridges the junction between two other parts of the case. However, it would be very difficult and hence expensive to manufacture complex seals having multiple branches or loops. Moreover, such seals would have very little versatility because they could no longer be used after a change was made to any one of the multiple parts of the case.